Wireless Internet Troubles on Macbook

[calicatty]

I have a 2 GHz MacBook3,1 with Intel Core 2 Duo.
My router is 2Wire.
My firewall allows all incoming connections.
My wireless card type is AirPort Extreme (0x14E4, 0x88) -- not sure if that matters.
And of course, I use Leopard.

Anyways, my internet connection has been shaky ever since I bought the computer (January). I always assumed it was my NETGEAR router, because everything worked fine when I was at my university. However, I found out that if I used my computer for too long at the university, my internet went out again. I just moved to a place that uses 2WIRE as a router, and voila, even though it worked fine for the first day/night, everything went downhill after that.

What internet problems am I having? Here are some examples:

Browsers claim I'm not connected to the internet:




Images don't load:


Pings don't work:






I already used IceClean to clean up my Mac, as well as Safari specifically. I looked at the DNS servers page for a while (because a few message boards said that clearing up the DNS servers would help things, but only one is listed). I restarted the router. I restarted AirPort.

Help!!

[Satcomer]

Open System Preferences->Network and then create a new location and click on apply. The "Automatic" function in Network is broken in my opinion.